The present invention relates to a suspension system for suspending wheels, and more particularly to a wheel suspension system which is capable of decreasing noises caused by inputs inputted from a road to wheels of a vehicle.
Japanese Published Utility Model Application No. 58-12008 has proposed a trailing arm type wheel suspension system in that a movement of an axle for each wheel is limited in the toe direction by a trailing arm which has a shape of extending in the vehicle longitudinal direction and of becoming wider from a rear position toward a front position in the vehicle longitudinal direction. A front portion of the trailing arm is rotatably connected to a shaft extending in the vehicle lateral direction through each of vehicle body brackets provided at both ends of the shaft. A rear portion of the trailing arm is elastically supported by a leaf spring provided under the trailing arm.
Other trailing arm type wheel suspension system has been proposed such that a pair of torsion bar cases extending in the vehicle lateral direction are connected to lateral outside portions of a vehicle body through a torsion bar which is connected through serrations to the lateral inside portions of torsion bar cases and extends in the lateral outside direction of the torsion bar cases. Further, the lateral inside portion of the torsion bar cases are connected to a bottom surface of the lateral inside portion of the vehicle body through bush, and a front portion of each trailing arm is rotatably connected to the vehicle body.
These suspension systems are capable of preventing the vibrations generated at wheels and axle members due to the road input from being directly transferred to a vehicle body, by utilizing a bending reaction force of the leaf spring or a torsional reaction force of the torsion bar as a spring element.